The remarkable selectivity of the 2-arylquinoline-based acyl hydrazones toward copper salts: exploration of their catalytic applications in the copper catalysed N-arylation of indole derivatives and C1-alkynylation of tetrahydroisoquinolines via the A3 reaction

Abstract

Ligands promoting copper-catalysed coupling reactions have received increasing attention because of their ability to enhance the catalytic activity of copper, making these reactions applicable in different fields such as drugs, pharmaceutically interesting molecules, and organic materials. Herein, we reported the synthesis and characterization of different selective 2-arylquinoline-based acyl hydrazones toward copper(I) salts. We explored the scope of the catalytic system based on copper/acyl hydrazones in the catalysis of C–N bond formation between N-heterocycles, specifically indoles, pyrroles and carbazoles, and aryl iodides as well as redox-A³ coupling of tetrahydroisoquinolines, terminal alkynes, and aldehydes.